1
0
Fork 0
alistair23-linux/lib
Peter Zijlstra f16b34aa13 lib: proportion: fix underflow in prop_norm_percpu()
Zhe Jiang noticed that its possible to underflow pl->events in
prop_norm_percpu() when the value returned by percpu_counter_read() is less
than the error on that read and the period delay > 1.  In that case half might
not trigger the batch increment and the value will be identical on the next
iteration, causing the same half to be subtracted again and again.

Fix this by rewriting the division as a single subtraction instead of a
subtraction loop and using percpu_counter_sum() when the value returned by
percpu_counter_read() is smaller than the error.

The latter is still needed if we want pl->events to shrink properly in the
error region.

[akpm@linux-foundation.org: cleanups]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Jiang Zhe <zhe.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-23 12:54:37 -08:00
..
lzo lzo: add some missing casts 2007-07-31 15:39:37 -07:00
reed_solomon [MTD] [NAND] Replace -1 with -EBADMSG in nand error correction code 2007-10-20 22:30:54 +01:00
zlib_deflate [PATCH] zlib_inflate: Upgrade library code to a recent version 2006-06-22 15:05:58 -07:00
zlib_inflate [ZLIB]: Fix external builds of zlib_inflate code. 2007-10-11 22:17:20 -07:00
.gitignore Add some basic .gitignore files 2005-10-18 08:26:15 -07:00
Kconfig Introduce CONFIG_CHECK_SIGNATURE 2007-08-22 19:52:45 -07:00
Kconfig.debug Blackfin arch: punt CONFIG_BFIN -- we already have CONFIG_BLACKFIN 2007-11-23 14:28:44 +08:00
Makefile lib: move bitmap.o from lib-y to obj-y. 2007-11-14 18:45:37 -08:00
argv_split.c LIB: Replace inappropriate include of <linux/bug.h> 2007-10-20 00:26:10 +02:00
audit.c [PATCH] audit signal recipients 2007-05-11 05:38:25 -04:00
bitmap.c Fix bitmap_scnlistprintf for empty masks 2007-11-05 15:12:32 -08:00
bitrev.c [PATCH] add MODULE_* attributes to bit reversal library 2006-12-10 10:07:52 -08:00
bug.c generic bug: use show_regs() instead of dump_stack() 2007-07-16 09:05:51 -07:00
bust_spinlocks.c handle recursive calls to bust_spinlocks() 2007-10-17 08:42:56 -07:00
check_signature.c uninline check_signature() 2007-07-16 09:05:50 -07:00
cmdline.c [PATCH] Numerous fixes to kernel-doc info in source files. 2007-02-11 10:51:32 -08:00
cpumask.c Safer nr_node_ids and nr_node_ids determination and initial values 2007-05-07 12:12:51 -07:00
crc-ccitt.c [PATCH] kernel-doc for lib/crc*.c 2006-06-25 10:01:20 -07:00
crc-itu-t.c CRC ITU-T V.41 2007-05-10 18:24:13 +02:00
crc7.c CRC7 support 2007-07-17 10:23:04 -07:00
crc16.c [PATCH] kernel-doc for lib/crc*.c 2006-06-25 10:01:20 -07:00
crc32.c Replace __attribute_pure__ with __pure 2007-10-18 14:37:32 -07:00
crc32defs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ctype.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
debug_locks.c [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
dec_and_lock.c [PATCH] atomic: dec_and_lock use atomic primitives 2006-01-08 20:13:48 -08:00
devres.c iomap: implement pcim_iounmap_regions() 2007-04-28 14:15:58 -04:00
div64.c [S390]: Fix build on 31-bit. 2007-04-25 22:28:53 -07:00
dump_stack.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
extable.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
fault-inject.c fault_inject: silence a warning 2007-07-24 12:24:59 -07:00
find_next_bit.c [PATCH] bitops: generic ext2_{set,clear,test,find_first_zero,find_next_zero}_bit() 2006-03-26 08:57:11 -08:00
gen_crc32table.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
genalloc.c Slab allocators: Replace explicit zeroing with __GFP_ZERO 2007-07-17 10:23:02 -07:00
halfmd4.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
hexdump.c hexdump: don't print bytes with bit 7 set 2007-11-29 09:24:53 -08:00
hweight.c remove asm/bitops.h includes 2007-10-19 11:53:41 -07:00
idr.c Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
inflate.c [PATCH] x86-64: deflate inflate_dynamic too 2007-05-02 19:27:15 +02:00
int_sqrt.c [PATCH] lib: Fix bug in int_sqrt() for 64 bit longs 2006-02-03 08:32:08 -08:00
iomap.c lib/iomap.c:bad_io_access(): print 0x hex prefix 2007-10-17 08:42:57 -07:00
iomap_copy.c [PATCH] add __iowrite64_copy 2006-06-20 20:24:58 -07:00
ioremap.c lib/ioremap.c should #include <linux/io.h> 2007-10-17 08:42:50 -07:00
irq_regs.c [PATCH] irq_reqs: export __irq_regs 2006-10-06 08:53:40 -07:00
kasprintf.c lib: move kasprintf to a separate file 2007-07-31 15:39:39 -07:00
kernel_lock.c spelling fixes: lib/ 2007-10-20 01:29:18 +02:00
klist.c Driver core: Don't call put methods while holding a spinlock 2006-09-25 21:08:40 -07:00
kobject.c kobject: fix the documentation of how kobject_set_name works 2007-12-17 10:33:18 -08:00
kobject_uevent.c Fix misspellings of "system", "controller", "interrupt" and "necessary". 2007-10-19 23:10:43 +02:00
kref.c kref: fix CPU ordering with respect to krefs 2007-04-27 10:57:29 -07:00
libcrc32c.c [LIB] crc32c: Keep intermediate crc state in cpu order 2007-11-08 21:34:09 +08:00
list_debug.c [PATCH] More list debugging context 2006-12-07 08:39:35 -08:00
locking-selftest-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-mutex.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rsem.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wsem.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest.c [PATCH] lockdep: show more details about self-test failures 2006-12-07 08:39:43 -08:00
parser.c [AFS]: Make the match_*() functions take const options. 2007-05-03 03:10:39 -07:00
percpu_counter.c Add irq protection in the percpu-counters cpu-hotplug-callback path 2007-10-19 11:53:44 -07:00
plist.c [PATCH] pi-futex: add plist implementation 2006-06-27 17:32:46 -07:00
prio_heap.c Fix cpusets update_cpumask 2007-10-19 11:53:41 -07:00
prio_tree.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
proportions.c lib: proportion: fix underflow in prop_norm_percpu() 2007-12-23 12:54:37 -08:00
radix-tree.c avoid negative (and full-width) shifts in radix-tree.c 2007-10-17 08:42:56 -07:00
random32.c [PATCH] severing module.h->sched.h 2006-12-04 02:00:22 -05:00
rbtree.c [PATCH] rbtree: fixed reversed RB_EMPTY_NODE and rb_next/prev 2006-09-30 20:26:56 +02:00
reciprocal_div.c [PATCH] SLAB: use a multiply instead of a divide in obj_to_index() 2006-12-13 09:05:49 -08:00
rwsem-spinlock.c Lockdep: add lockdep_set_class_and_subclass() and lockdep_set_subclass() 2006-10-11 01:45:14 -04:00
rwsem.c sched: mark rwsem functions as __sched for wchan/profiling 2007-12-18 15:21:13 +01:00
semaphore-sleepers.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
sha1.c [PATCH] Numerous fixes to kernel-doc info in source files. 2007-02-11 10:51:32 -08:00
smp_processor_id.c [PATCH] fix missing includes 2005-10-30 17:37:32 -08:00
sort.c lib/sort.c optimization 2007-10-17 08:42:52 -07:00
spinlock_debug.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00
string.c [STRING]: Move strcasecmp/strncasecmp to lib/string.c 2007-04-26 01:54:39 -07:00
swiotlb.c Update swiotlb to use sg helpers 2007-10-22 21:19:58 +02:00
textsearch.c [TEXTSEARCH]: Do not allow zero length patterns in the textsearch infrastructure 2007-12-01 00:03:52 +11:00
ts_bm.c [TEXTSEARCH]: Fix Boyer Moore initialization bug 2006-08-22 14:33:58 -07:00
ts_fsm.c [PATCH] lib/ts_fsm.c: constify structs 2006-09-29 09:18:23 -07:00
ts_kmp.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
vsprintf.c lib: move kasprintf to a separate file 2007-07-31 15:39:39 -07:00